The Internet Encyclopedia (Volume 3)

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514 USABILITYTESTING:ANEVALUATIONPROCESS FORINTERNETCOMMUNICATIONS

human computer interaction. Baddeley (1999) provides

a succinct overview of memory, and Barsalou (1992)

provides an overview of cognitive psychology. Cogni-

tive science provides a strong theoretical foundation for

building deeper understandings of how users process all

forms of information. Osherson (1995) edited a multi-

volume compendium with individual chapters by leading

researchers in cognitive science.

Carefully developed, research and evaluations can pro-

vide heuristics or guidelines for developing communica-

tions and products. For example, the National Cancer In-

stitute’s (NCI) Web site (n.d.) provides an orientation to

usability testing and then provides specific research-based

guidelines. The NCI organized the guidelines around cat-

egories: design process, design considerations, content/

content organizations, titles/headings, page length, page

layout, font/text size, reading and scanning/links, graph-

ics, search, navigation, software/hardware, and accessibil-

ity. For each guideline, the NCI had a group of interface

and Wed design researchers develop a rating scale and

rate the support of the guideline based on research and

evaluation. The site provides an explanation of the rating

process and criteria used.

USABILITY METHODOLOGIES

Usability testing methodologies emerged in the early

1980s as companies increasingly recognized customers

were having trouble with computers. The methodologies

enable usability practitioners to identify problems with

hardware, software, and computer content as users inter-

act with the technology.

By early 2002, usability testing of e-commerce Web

sites became exceedingly critical. Unless e-commerce sites

are easy to use, consumers will not stay long enough to

purchase items (Nielsen & Norman, 2000b).

Usability protocols include Web site evaluations by

software engineers and site developers, usability and hu-

man factors experts, and intended users or consumers.

They take many forms. For example, software engineers

may conduct cognitive walkthroughs of a conceptual Web

site to visualize possible discrepancies between online

tasks and users’ expectations of those tasks. Usability ex-

perts may engage in a structured examination of a Web

site prototype, or a heuristic evaluation, to assess its us-

ability against generally accepted standards. Software en-

gineers, usability professionals, and users may assess a

Web site prototype collaboratively in pluralistic usability

walkthroughs. In addition, variations on these protocols

range from simple usability inspections and site design re-

views to complex distance testing with sophisticated soft-

ware programs over the Internet.

In recent years, a variety of automated ways of as-

sessing Web site design have been proposed. Among the

more commonly used is click-stream analysis (Burton &

Walther, 2001; Lee & Podlaseck, 2000; Murphy, Hofacker,

& Bennett, 2001) and server logging programs. Usability

practitioners install a software program on the server or

individual computer that captures keystrokes and page

visits as a user navigates the Web site. The programs pro-

vide various data, such as the more frequently used pages,

the time spent on individual pages, and the least visited

pages. Usability practitioners vary in their use of such pro-

grams. That said, such programs provide promise in giv-

ing an alternative, unobtrusive measure of users’ interac-

tions with Web sites.

Although usability practitioners can use many meth-

ods, the following discussion elaborates on four examples

of usability techniques. They are representative protocols

modeling the range of methodologies. They are card sort-

ing, contextual inquiry, heuristic evaluation (expert re-

view), and verbal protocol analysis (see Table 2 for a list

of references related to each protocol).

Card Sorting

Web sites often fail to transfer information to consumers

because developers and users have different frames of

reference—they use terms differently, may not agree on

the meaning of page labels, or they may organize informa-

tion differently. Card sorting provides insights into how

users classify, label, and organize information. Web site

developers can use these insights to design, label, and

structure a Web site to match users’ frames of reference.

Table 2Usability Testing Methods and Related References

METHOD RESOURCES

Card sorting Fuccella (1997); Fuccella & Pizzolato (1998); Koubek & Mountjoy (1991);

Martin (1999a, 1999b, 1999c); McDonald, Dearholt, Papp, &

Schvaneveldt (1986); Neilsen (1993, 2000)

Contextual inquiry Beabes & Flanders (n.d.); Beyer & Holtzblatt (1995); Holtzblatt & Jones (1993)

Heuristic evaluation IBM (2001); Nielsen (1994); Van der Geest & Spyridakis (2000)

Verbal protocol analysis Bailey (1996); Barum (2002); Ericsson & Simon (1984, 1993); National

Cancer Insitute (2001); Preece (1993); Nielsen (1993, 2000a, 2000b);

Redish & Dumas (1994); Rosson & Carroll (2002); Rubin (1994); van

Someren, Barnard, & Sandberg (1994)

Usability testing Bailey (1996); National Cancer Institute (2001); Preece (1993); Nielsen

(1993); Dumas & Redish (1994); Rosson & Carroll; (2002), Rubin (1994);

Society for Technical Communication (2002); Usability Professionals

Association (2002)